JP2002298104A - Method for manufacturing rfid label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve working efficiency by performing integrated works for each process with rewinding an adhesive tape for die-mounting rolled in a reel shape as it is and to provide a method for manufacturing a thin-type RFID label with fully protecting a wire from outside force by removing protrusion of a wire bonding part. SOLUTION: A strip shaped antenna base material 2 and semiconductor chip 2 are adhered to a surface of the adhesive tape for die-mounting 1 rolled in a reel shape with rewinding the tape 1 starting from its end, and the wire 4 such as a gold wire is bonded between an electrode terminal of the chip 3 and the material 2. Then the bonded part of the wire is crushed for removing the protrusion and liquid resin 5 is dropped on the surface and cured and additionally a protection tape 6 is adhered to the surface and wound in a reel shape. Such a series of processes is integrally performed with conveying the tape 1 at a constant speed or intermittently.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an RFID (Radio Frequency ID
The present invention relates to a method for manufacturing an RFID label used in an automatic recognition and identification system called "tification". More specifically, a series of RFID labels manufactured by attaching an antenna substrate and a semiconductor chip to an adhesive tape for die mounting are manufactured in a series corresponding to the supply / discharge form of a long adhesive tape for die mounting wound in a reel shape. And a consistent manufacturing method for performing each of the steps.

[0002]

2. Description of the Related Art Conventionally, in order to manufacture an RFID label of a type in which an antenna substrate and a semiconductor chip are attached to an adhesive tape and both are connected by a wire such as a gold wire, a manufacturing process as shown in FIG. Manufactured. That is,
The die mount adhesive tape 1 to which the antenna substrate 2 and the semiconductor chip (die) 3 are adhered is rewound from the reel-shaped one, and the antenna substrate 2 is first adhered. The antenna substrate 2 also needs a certain thickness of a dielectric material, and as shown in FIGS. 4 and 5, a cross-sectional explanatory view of a completed RFID label, a conductive film is generally formed on the surface of the glass epoxy substrate 2a or the like. The antenna substrate 2b is used as the antenna substrate 2, and a through hole is formed in a part of the antenna substrate 2. The semiconductor chip (die) 3 can be mounted in the through hole. For this reason, the antenna substrate 2 cannot be supplied in a state of being wound in a reel shape, but is supplied in the form of a strip-shaped sheet having a certain size.

On the other hand, the die mount adhesive tape 1 to which the antenna substrate 2 and the semiconductor chip 3 are adhered is wound in a reel shape, sequentially rewound, and the antenna substrate 2 is adhered, and has substantially the same size as the antenna substrate 1. The pieces are cut to a fixed size and each is sent to the next step. That is, FIG.
As shown in FIG. 2, a die mounting step of mounting the semiconductor chip 3 on the die mounting adhesive tape 1 exposed through the through hole of the antenna substrate, a method of forming a gold wire or the like between each electrode terminal of the semiconductor chip 3 and the antenna substrate 2. A step of wire-bonding the wire 4, a liquid resin 5 made of, for example, epoxy resin or the like on the wire-bonded surface;
The RFID label can be shipped by sequentially performing a process of dropping and applying, a post-curing process of curing at about 90 ° C., a process of attaching a protective adhesive tape 6 to the surface thereof, and a step of winding the protective adhesive tape 6. State.

[0004]

As described above, an RF for assembling a conventional antenna substrate and a die on an adhesive tape is used.
In the method of manufacturing an ID label, an adhesive tape for die mounting to which an antenna substrate is attached is cut in accordance with the size of the antenna substrate, and each process is performed in a batch manner.
Therefore, in each process, it is necessary to perform positioning for each substrate, and a large-scale apparatus is required, such as a mechanism for sending the substrate to the next process. Further, there is a problem that work is stagnated in some processes and production efficiency is low.

Further, as described above, after the wire bonding, a resin is dropped and cured in order to protect the bonding portion, but the wire bonding portion is formed in a direction perpendicular to the semiconductor chip (die). Therefore, when the wire in that portion is to be protected, as shown in FIG. 4, the resin in the semiconductor chip portion rises (see 5a in FIG. 4), and becomes considerably thicker than the antenna substrate 2 portion. Therefore, there is a problem that the thickness of the RFID label is not uniform and becomes thick. on the other hand,
If the drop of the liquid resin is made thin and uniform, as shown in FIG. 5, the wire of the wire bonding portion of the semiconductor chip is exposed from the resin layer (see 4a of FIG. 5), and the wire is easily cut by an external force. There's a problem.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a problem, and to perform each step in an integrated operation while rewinding a die-mounted adhesive tape wound in a reel form as it is. In addition to improving work efficiency, eliminating the protrusion of the wire bond portion completely protects the wire from external forces while reducing the thickness of the RFI.
It is to provide a method for manufacturing a D label.

[0007]

According to a method of manufacturing an RFID label according to the present invention, a strip having a through-hole formed in the surface of a die-mount adhesive tape wound on a reel while rewinding the tape from an end thereof. -Shaped antenna substrates are sequentially attached, a semiconductor chip is mounted on the surface of the adhesive tape for die mounting exposed through the through holes of the antenna substrate, and the electrode terminals of the semiconductor chip and the antenna substrate are connected by wire bonding. Then, the wire of the bonding portion is crushed to eliminate the projecting portion of the wire, a liquid resin is dropped on the wire bonding portion, and the wire resin is cured and sealed. The process is performed in an integrated process while rewinding and transporting the semiconductor chip mounting adhesive tape.

According to this method, each step is performed consistently while rewinding and transporting the die mount adhesive tape without cutting the die mount adhesive tape along the antenna substrate. There is no need to align the antenna substrate and the like, and there is no stagnation of semi-finished products in one process, so that it is possible to manufacture very efficiently. If the process requires more time than other processes, for example, when the curing time for sealing the wire bonding portion is longer, for example, lengthen the drying furnace for curing, and transport in the drying furnace. By doing so, each step can be performed continuously while the adhesive tape for die mounting is transported at a constant speed.

Furthermore, according to the present invention, since the wire is crushed at the bonding portion after the wire bonding, the protrusion of the wire at the bond portion is almost eliminated, the dripping of the liquid resin is reduced, and the thickness is reduced. However, the wire bonding portion can be completely covered. As a result, a thin RFID label with a parallel plate shape is obtained, and there is no protrusion of the wire.
There is no accident such as hitting something and cutting the wire when carrying, greatly improving reliability.

[0010]

Next, a method for manufacturing an RFID label according to the present invention will be described with reference to the drawings. The method for manufacturing an RFID label according to the present invention, as shown in FIG. 1 and the sectional view of the product in FIG. While rewinding, a strip-shaped antenna substrate 2 having a through hole formed on the surface of the tape 1 is sequentially attached. Then, the semiconductor chip 3 is mounted on the surface of the die mount adhesive tape 1 exposed through the through hole of the antenna substrate 2 (see FIG. 2), and a gold wire is provided between the electrode terminal of the semiconductor chip 3 and the antenna substrate 2. The wires 4 are bonded to each other to bond them.

Next, the wire of the bonding portion is crushed to eliminate the projecting portion of the wire, and the resin is sealed by dropping and curing the liquid resin 5 on the wire bonding portion. Then, the protective tape 6 is stuck on the surface and wound on a reel. This series of steps is performed in an integrated process while rewinding and transporting the adhesive tape for semiconductor chip mounting, and by crushing the aforementioned wire bonding part, the projecting part of the wire is eliminated, and the entire wire part is covered with resin. The feature is that it is made thinner.

The pressure-sensitive adhesive tape 1 for die mounting is made of, for example, polyimide and has a length of about 20 to 30 mm and a thickness of about 0.06 mm, and is wound into a reel. Therefore, if you pull one end,
It can be rewound and transported sequentially. The antenna substrate 2 is used because a dielectric substrate such as a glass epoxy substrate 2a having a thickness of about 0.14 mm is inexpensive, and a conductive film 2b such as Cu or Al is provided on the entire surface by printing or the like. I have. And, for example, 20-30
In order to cut the semiconductor chip 3 at the center while cutting it into a strip having a size of about mm × 60 mm,
A through hole of about 2 mm × 3 mm is formed. The antenna substrate 2 is used, for example, to receive a wireless question from a question device (not shown) and wirelessly transmit the answer sent from the semiconductor chip 3 to the question.

The semiconductor chip 3 is formed to store a predetermined digital value that can be used for a number of purposes to identify individual objects or individuals to which the RFID is attached. Various data can be written and read.

The semiconductor chip 3 and the antenna substrate 2 are connected so that signals can be transmitted and received between the semiconductor chip 3 and a wire 4 such as a gold wire by wire bonding. Wire bonding with the semiconductor chip 3 is performed by pressing the tip of a wire having a ball formed at the tip onto the electrode terminal of the semiconductor chip 3 while applying ultrasonic waves.
Bonding is performed by setting the temperature to about 0 to 110 ° C. The normal bonding portion remains wire-bonded, but in this state, the wire 4 extending from the bonding portion extends in a direction perpendicular to the surface of the semiconductor chip 3. Therefore, in the present invention, a crushing step is provided after this. That is, by clamping the bonded wire 4 to the thickness of the antenna substrate 2, the wire 4 is crushed so as to extend right from the bonding portion. And
The other end of the wire 4 is connected to the conductor film 2 on the surface of the antenna substrate 2.
The wire bonding on the antenna substrate side is performed by stitch bonding on a. In this way, the conductor film 2a
Is bonded without protruding to the upper portion.

Thereafter, a resin 5 made of a liquid epoxy resin or the like is dropped so as to cover the entire surface of the semiconductor chip and the wire bonding portion of the antenna substrate 2, and is cured by heating at about 90 ° C. for about 60 minutes. As shown in FIG. 2, a resin layer 5 which completely covers the gap between the antenna substrate and the two semiconductor chips 3 and the wire bonding portion is formed. This curing step (post-curing) takes longer than other steps, but forms a long drying oven and cures as the die mount adhesive tape 1 passes at a constant speed or intermittently. By forming them, work can be continuously performed without providing a waiting time in each step.

Thereafter, the protective adhesive tape 6 is stuck on the surface and wound in a reel shape, so that it can be manufactured in a state ready for shipment.

According to the present invention, the work of each step is carried out while cutting the adhesive tape for die mounting without cutting it, and while it is rewound as it is long and conveyed at a constant speed or intermittently. It is not necessary to align the antenna substrates one by one, and moreover, each process can be performed consistently without a semi-finished product staying in one process. As a result, the production efficiency of the entire production line is improved.

Further, according to the present invention, since the step of crushing the bonding portion after the wire bonding is performed, the projecting portion of the wire is eliminated, so that even if the entire wire portion is covered with the resin, the very Thin RF
It becomes an ID label. Moreover, since the wire portion is completely covered with resin, the resistance to external force is improved,
The reliability is greatly improved.

[0019]

As described above, according to the present invention, a very thin and highly reliable RFID label can be obtained at a very low cost due to an improvement in production efficiency.

[Brief description of the drawings]

FIG. 1 is a view schematically showing a manufacturing process of an RFID label according to the present invention.

FIG. 2 is an explanatory sectional view of an RFID label manufactured according to the present invention.

FIG. 3 is a view schematically showing a manufacturing process of a conventional RFID label.

FIG. 4 is an explanatory cross-sectional view of an RFID label manufactured by a conventional method.

FIG. 5 is an explanatory sectional view of an RFID label in which a resin layer is thinned by a conventional method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Adhesive tape for die mounts 2 Antenna substrate 3 Semiconductor chip 4 Wire 5 Resin 6 Protective adhesive tape

Claims (1)

[Claims] 1. A strip-shaped antenna substrate having a through-hole formed on the surface of a tape is sequentially attached to a die-mount adhesive tape wound in a reel shape while rewinding the tape from an end portion thereof. A semiconductor chip is mounted on the die mount adhesive tape surface exposed by the hole,
By connecting the electrode terminal of the semiconductor chip and the antenna substrate by wire bonding, crushing the wire of the bonding portion to eliminate the projecting portion of the wire, dropping a liquid resin on the wire bonding portion and curing the resin. A method of manufacturing an RFID label, wherein a series of steps of sealing, attaching a protective tape to the surface, and winding the tape in a reel shape are performed in an integrated step while unwinding and transporting the adhesive tape for mounting a semiconductor chip.